Abstract: The numerical simulation has been carried out to investigate the effect of endwall fence on the secondary flow in a compressor cascade.The results show that the boundary layer fences can reduce the strong cross-flow from the pressure surface to the suction surface near the cascade endwall.A counter-rotating streamwise vortex is formed over the fence and the strength of the passage vortex is diminished.It is found that the fences are most effective when they are located 30 percent pitchwise from the pressure surface of the blade.For the optimum endwall fence location,the cascade loss can be reduced 7～9 percent compared with the conventional cascade.